Improvement in truss-g-irder bridges



pero eri-pa DAVID HAMMOND AND JOB ABBOTT, OF CANTON, OHIO.

Letters Patent'No. 102,394, dated April 26, 187 O.

IMPROVEMENT IN TRUSS-iG-IRDER BRIDGES.

The Schedule referred to in these 4Letters Patent and making part of the same.

vTo all whom it may concern: A

Be it known that we, DAVID HAMMOND and Jon Anno'll, of Oantolnjn the county ot' Stark and State of Ohio, have invented certain'new and useful Improvements in Truss- Girder Bridges; and we do hereby declare that the following is a i'ull, clear, and exact description ot our invention, reference being had to the accompanying drawings forming a part of this specification and to the letters of reference marked thereon, of which drawings Figure l is an elevation of a"bridge .showing our improvements. l

Figure 2 is a partial plan, vshowing the arrangement of upper and lower lateral bracing.

Figure 3 is a cross-section of the bridge.

Figure 4 is a detail section of upper chord and side view of upper lateral connection. 1

Figure 5 is a side view Y of upper chord and crosssection of upper lateral compression member.

Figure 6 isa longitudinal section taken tln'ougl center of upperchord'and lateral. Figures 7 arc'frontand rear cud and sideviews of head-block for upper lateral compression. member.

Figures S are side views-ot` adjustable chord-splice and end view of one chord and bolt. f

Figures 9 are details of'bent eye-bolt for splice.

Figure 10 is side 'viewiof a xnodied form of splice.

Figures llvarc detail views oi' eye-bolt and connecting-bolt for splice.

Figure l2 is a perspective view, showing the niode of combining the posts, lower chords, braces and floor-beams. f'

Figure 13 .is a vertical longitudinal section of the;

truss-shoe.

Figure 14 is a longitudinal section of thc trussshoe, taken through the adjusting wedges.-

Figure 15 is a plan of the truss-shoe.

Figure 16 is an end view ofthe counter-brace end of the clamping-piece at the intersection oil the main and counter-braces. l i

Figure 17 is an end view of the main-brace end of the same. 'Y

-1 `igures18 are side View and plan of the clamping, piece. v

Figure 19 is a perspective view, showing the Inode of combining the post and 4lower rail of the sidewalk i'cnce.

Figures 20 are side and end views of connectio between fence-post and upper rail of fence.

Figure 21 is a perspective View, showing manner of uniting fence to floor-beam.

Figure 22 is a detail plan, showing mode of combining a tubular lateral with the chords ofthe truss.

Our invention consists,ltirst,.inA forming a point of suspension from which to support the centers of the sections of the upper 'or lower chords in a truss having tensonal braces, by means of a clamping piece, so secured to the rnain and counter-lnjaccs as to be firmly held against sliding on either of them, in case of the slacking of the other, whereby the main and counter-braces may be used as a part o'f a suspension truss for supporting the centers of the sections of the chords without any increase of material ill said braces.

Our invention consists, secondly, in arrangement ofthe chord ends, adjusting wedges, and gird'er-shoes, whereby we obtain a very economical Aand strong con- ,nection, in which a considerable adjustment ofthe length of either or both chords may be el'ectedfby loosening or tightening the nutsou the adjusting wedges, in order to allow for any inaccuracies in con struction. l

Our invention consists, thirdly, in the use of a pin having its ends itted in plates secured to the platochords of a truss, and with its-ends abutting against the inner faces of the chords, whereby we obtain a pin-connectiougfor the main and counter-braces of the truss with the lower chords, and a pin-bearing for the post, if desired, and a distance-piece, against which` the chords arc clamped, to insure the proper space between them, without the necessity of using link lchords, or -oi' boring piu'holcs Vin the plato-chords, and are enabled to better adapt the cost ot construcf tion to the requirements of road bridges.

Our invention consists, fourthly, inthe novel inodey of securing the ends ofthe lateral compressive 1ne1n' f ber, and lateral braces to each other and to the chords, vand inthe novel mode ofv constructing a wrought-iron connection for a tubular lateral compressive member bases of the'posts of thc truss, which rest on -the vlower chords, whereby the base of the post also serves as the line of support for the floor-beam on the chords, and the post-base, chords, and Hoor-beams are iirmly clamped together, and are prevented from ,slipping ou each other, by the same bolts which carry the floorbeams.

Our invention consists, seventhly, in the use of a saddle-block over the intersection of the upper chord and inclined end-strut of a truss, in which the weight of the central part of the bridge is sustained by rods running from the ends of the upper chords to the oppositecorner of the first full section, whereby the .iunited by bolts, 4 4, passing through intervening clamping pieces in an ordinary'manner.

The end-strut consists of two channel-irons, D D, which are united by the plates E E,Yriveted on at the sides, as shown.

The' channel-irons A A and .D D are beveled oii and abut against each other.

The plate B is extended over the irons D D, and

l the lower plate E extends under the irons A A, where they are riveted, as shown.

The saddle-blocks F F set over the intersection of f the upper chords and end-struts, and the nut-blocks -G G are placed on the plate` B, where they areprevented from slipping by teats on their lower faces,

which it in holes in the plate B.

The end-struts rest on the inclined faces of the truss-shoes B R, and are prevented from slipping on said shoes by the face-danges 3 3, (see iigs.- 13 and A15,) which fit inthe'ehannel-irons D D.

' The chords Q Q are made of plate-iron set up edgewise and parallel to each other, and pass through slots cut in the lower plate E, between the channel-irons D D into slots formed in'the shoes R R.

The shoe R consists of the base-plates 5 andside walls 7 7, and cross -walls 6 6; the walls 7 7 having the slots for the chords Q Q formed iu them, and the beveled faces of the walls 7 7 'and cross` walls 6 6 forming the seat ihr the end-struts.

'lhe adjusting wedges 'a 'v consist of the wedge part u, at the small end of which is the I threaded bolt e, provided with a nut, w.

The slots x and y' are cut at'A the centers ofthe i cords Q Q, the slot a: being cut for the bearing' face of the wedge n, and the slot c being eut to allow of the passage of the bolt end v of the wedge.

The slotted holes'f.' z are cut in each wall 7 of the shoe', and a round hole is bored in the opposite wall,

as shown.

The wedges a 'v are inserted in opposite directions in the-shoe, so as to throw the strain from the chords at both sides of thc shoe; and thc wedges are iliade of sufficient length to pass through both side walls oi' the shoe so as toallow of `a considerable side draft of the wedge, and consequent adjustment in the length of the chords.

'Ihe bases P of the posts 0A restl on the chords Q Q, and are held from sliding off by the anges on their lower sides, as shown in iig. 12. A l

'I`he plates c c are secured, on the inner sides of the chords Q Q, by rivets c e,aud have holes bored in them of a suitable size to admit the pin f, which passes through eyes formed at the ends of the main braces I I and counter-brace J, and abuts againstthe chords QQ at each end, the said chords being held up to the pin f by the bolt or rivets d d at each4 side of said piu, and

extending through both chords Q Q and plates c e.

The braces I I J pass up through the post-bases l), or at the sides of said bases, as may be found desirable, and up between the channel-irons A A, through holes formed in the plate B and blocks F G, where they are secured by nuts, as shown.

The end bracesI I pass between the channel-irons A, through the plate B and inclined 4face of the sad-4 dle-block F in such position as to cause the plane of .the rods I I to cut the beveled plane of intersection of the channel-irons A A and DV D at or near the top of the upper chord, so that the strain from said rods is thrown onto both the upper chord and end-strut, and any tendency of one to slide on the other is obviated.` l

rIhe posts C are made of the Ihcenix column, and set ou the bases P, as shown, being h eld from slipping by the raised interior portion of the base, as shown in iig. 12. i

They may be placed with the plane of two opposite flanges parallel with the chords, as shown in iig. 12,01'

withV two opposite faces parallel with the chords, asA

shown iu figs 1 aud 4, as is found desirable, and have the cast head O constructed as shown, to forni a bearing for the upper chords.

'Ihe upper lateral compressive members, shown in drawings, which form a part of the lateral bracing,

uniting the upper chords of the two girders vforming the bridge, are made of four angle-irons, Y YY Y, which are u nited by rivets passing 4through the legs of the angle-irons'and thimbles interposed between said legs in such a manner as to form` a swelled column of the form and section'shown in figs. 2, 3, and 5. 4

Ihe head blockj is made`ot` a +form at one end, and the angle-irons Y Y are riveted between the ,armsjjzjaj as shown in figs. 4, 5, and (i.

rIhe head 7'5 is made to lit in the channel-iron A, shown in fig. 4, and the circular hole j is formed in the face of this head to receive the eyes at the ends ofthe lateral braces Z Z, which come ont through the slots jljl, as shown in Q. 6. l

'Ihe bolt k passes through a hole in the block j, through the eyes on the laterals Z Z, and through `the'chords A A, as shown, thus securing the chords and later-als together in a very simple manner.

It' desired, the head j5 could be cut away at the sides of the hole j, as indicated by dotted lines ings. 7, and as shown in fig. 4, in order to allow of' theeyes of the braces Z Z, heiligA slipped into position i after the compressive member Y Y had been put in i place, but the first described construction is preferable.

Where the bridge is to be loaded on the sections of' the lower chord, by laying the `floor joist Vacross the bridge and on the lower chords, vor wl1ere-the.load is carried by Boor-beams at theposts and at the centers of the sections, it is desirable to obtain a support for the center ot thesectious of the lower chords, as shown at left-hand side oi' iig. 1, and for this purpose the saddle-block r (see fig. 18) is placed on the main braces I I and counter-braces J and through it pass the rods- L L, onerod passing between each main brace and the counter-brace, andthe two rods passing between the chords Q Q into a cross-piece, 10, on which the chords Q Q rest, where they are secured by a head .or.

nuts, shown.

It is obvious thatlif' the saddleblock r were sim ply laid on 'the -braces I I J, it would sustain the chord-section, but that it would have a transverse strain ou the rods I I J. To prevent this, the clamps s and t are placed under the rods I I J, and clampingbolts are passedthrough these pieces, and the ends r "r2 of the saddle-block, by which means it is firmly vclamped'to both the main and center-braces, so that the strain from the rods L L only produce a tensional strain on the braces I I and J.

, Where the bridge is constructed as a deck-bridge, and the load is placed on the sections of the upper chords, the centers of the upper 'chords should he snpported, and for Vthis purpose a compression member, M, is introduced between lthe saddle-block lr, and a head-piece, N, placed under the chords A A, as shown in right-hand sideof fig. 1.

By clamping the saddle-block lr to the braces, the weight is taken from the center of the chord-sections and transferred to the braces, instead of being carried on the chords Vto the post and there transferred to the braces; consequentlyl thefstrain on said braces in either case is the saine, and fno increase o f material is re. quired in them.

' Vv'herethe bridge is to be loaded at the posts, and not on the sections of the chords, it is desirable to have the load appledin the lin'e'of the posts, and for this purpose the Hoor-beams vS are suspended under the chords Q Q, by means of a stirrup, "y, which encircles the beam and has its ends passed up through the post-base P, where they are secured by nuts h li, as shown in fig. 12. The stirrnp g is notched into the flanges of the beam S atll 11, so as to prevent the beainvfrom sliding in the stirrnp, audit is readily seen that when the nuts h h are drawn up tightly there is but little chance for any movement ot the post-base lor Hoor-beam on the chords.

Two bolts could be used in place of the stirrup g, which should pass through holes in the flanges of the beam, or down at the edges of the iianges into a crosspiece under the beam, but the construction shown is preferred.

lVhere the plates composing the chords Q Q are to be united, they can beA spliced with platesyin an ordinary manner, if desired, and where the splices are made at the posts, the splice-plates conldalso be used as the plates c c for the pin f; or, where itis desired to increase the thickness of metal in the chords, four plates can be used in the place of two, as is here represented, when the ends ofthe innerplates, Aat the points where the parts of the chords are united, can have the holes for the pinf formed in them, and will thus serve as the plates c' c.

It'may be desirable, however, to be able to adjust the length of the chords at the splices, and for this purpose two bent bolts, ZZ, having an eye, Z, at one end, and a 'thread and nut, l?, at the other end, are secured in the ends vof `the parts' Q Q of the chords, by bending the ends of the chords around the bolts l and lap-welding the end to the chord, when the two parts are united, as shown in iig. 8, and the length can be adjusted by the nuts l l?, as is readily seen.

A modified form of this splice is shown in g. 10, in

which'two double-eyed bolts, m m, are secured in the" .but if no licor-beams are used a light Phoenix column, a, can be used, as shown in iigs. 2 and 22, to which the. lateral braces b b can be riveted, as there shown.

In order to unite the column a to the chords, we take a 'U-shape'd piece of wrought-iron, q, and insert it iu the end of the column, where it can readily be' secured by rivets, as shown.`

The bolt q' passes through the end ofthe U and through the chords Q Q, thus. uniting the lateral bracing to the chord, and said bolt can also serve as the point of attachment for the end suspension-rod H and counter-brace J, the thimbles being placed on the bolt q', it desired, so as to forma solid connection for the chords, lateral bracing, suspension-rod, and counterbrace.

-When iron floor-beams are used, and it is desired to complete the iron superstructure independent of the wooden ilooring, the fence-posts TT are secured to the floor-beams S, by cutting notches p p Ainl the -ilanges of the beam, to admit one "leg of theangle-iron forming the posts, which are then secured in position S, under the fence-posts, as shown in fig. 21; or two bolts could be used, eachl passing through the leg of 'the angle-iron resting against the edges of the beamflanges, and through the. web of the-beam, one near ythe top flange and the other near thebottoni flange,

with; or the pieces p1 could be omitted in the irst shown, is the most desirable.

,The lower railpU-.of the fence is made of "angle-iron or. bar-iron, the angle-iron being preferable for long panels, and is riveted to the post T, together with one of the lattice bars Vas shown in iig. ,1 9, the h orizontal leg of the angle-iron being rounded off, as shown, and being arranged as shown, or in a reversed l position, as may be desired.` s

The upper end` ofoneleg of the postv is bent over,

iron fits onthe end of the post T, as shown.

W, as shown, a rivet being put through the coveringplate X, angle-iron W, andbent leg ofl post T, and the covering-plate being extended from one panel to the next, as shown in tig. 1.

The corner lattice-bar V is secured by a rivet passing-through the angle-iron W and post T, and the intermediate lattice-hars are riveted to the posts T T, the upper and lower rails W U, and to each other, as shown.

It is evident that the details of the connections of posts T T, rails U W, and lattice-bars V V, could be the lattice-bars oonldbe placed inside of the angleiron, if preferred, without affecting the genera-l plan of construction here shown. Y

It is also evident that the modes of' supporting the centers'of the sections of the chords herein described are equally applicable to arched trnssfgirders'in which posts. and crossed braces are used, and the posts serve as Well for suspension-rods as for compressive menibers of the trussing. 1`rWe are aware that auxiliary trusses have been formed in girders; hence we lay no claim to such auxseouring lthe ends ofthe chords in the girder-shoes but` hat we do cla-iin herein as new and of our invention, and desire to secure by Letters Patent, isv 1. Forming a point of suspension from which to support the sections of the upper or lower chords in trusses provided with tensional, main, and counterbraces, by means of a clamping-piece, so secured to said pieces at their intersection as to be held from slipping on either of them in case ofthe slackening of the other.

2. The combination of the shoe R, provided with the slots :t and y, and adj usting-'wedges u u, provided speciiied. Y y

Y3. The pin f, arranged in holes in the plates c c, or their equivalents, secured on the inner faces of the chords Q Q, the ends of said pin abutting against the inner faces of said chords, so that it serves as the distance-piece against which said chords are clamped,

substantially as and for the purpose specified.

clamping-bolts or rivets d d, and pin j, the several parts-being arranged substantially as and for the purpose specified.

5. The combination of the braces I I J, provided with eyes at their lower ends, pin j, plates c c, chords by a single bolt,`p2, passing 'through one leg of each.I angle-iron and the webV of the beam S, and through L filling-pieces pl, fitting in the` sides ofthe floor-beam when the notches p and pieces p1 could be dispensed construction' shown, but the first construction, as

as shown in iig. 20, and the upper rail W of angle- The covering-plate X is riveted on the angle-iron Isomewhat varied from those here described, or that'V Ailiary trusses; nor do we claim the use ot' a wedge for the slotted side walls 7 7, chords Q Q, provided with ywith the bolt-ends c, with nuts w, the several parts l being arranged substantially as and for the purpose 4. The combination 'of the chordsJQ Q, plates c c,

Q Q, and clamping-bolts or rivets d d, the severai parts being arranged substantially as and for the pur pose speeted.

6. .lheheadfblockj, provided with the cavity j and slots jij, when used in combination withthe lateral Y Y, braces Z Z, and bolt lc, the several parts being con- `struoted and arranged substantially as and for the purpose specified. i

postbase resting as a saddle-block on the upper edges of said chords, and the several parts being arranged substantially as and for the purpose specihed.

l 10. The notches 1l 11 in the flanges of the floor-A beam S, when acting in combination with the s tirrup g, to prevent the floor-beam from sliding vin said stir# `rup, substantially as and for the purpose spectied.

11. The saddle-blockF, when used in combination with the upper chord A B A, and strnt- D E D, and rods I I, substantially as and for the purpose specilied.

As evidence that we claim the bregoing, we have hereunto set our hands, in 4the presence. ot' two witnesses, this 8th day of November, A. D. 1869.

D. HAMMOND. JOB ABBOTT.

Witnesses:

A. R. MCKINLEY, WM. MOKINLEY, Jr. 

